Diagnosis and treatment of ADHD
The persistent and pervasive combination of hyperactive and abnormally restless, impulsive and unconcentrated behaviour from early age on is more common than chance alone would dictate, has a distinct hereditary component and can present serious problems for afflicted children and their families. Compared to their peers, children thus predisposed place greater demands on parenting skills and effort, and may put their social environments’ tolerance to the test. If the interaction between the child and its environment is caught in a negative spiral, this may threaten the child’s development and the psychosocial balance within its family. This may well have an adverse effect on the child’s social prognosis in the long run. Under such circumstances, the described condition is classified as attention deficit hyperactivity disorder, or ADHD. ADHD is often accompanied by other psychopathological conditions and is associated with an increased risk of addiction, involvement in accidents, antisocial and criminal behaviour. It is therefore regarded as a (childhood) psychiatric syndrome and as a disorder that requires therapy. In most cases, the clinical picture associated with ADHD is more complex than the mere combination of the three behavioural characteristics referred to above. Children with ADHD frequently lack social skills or have developmental problems in speech or motor control. About half of them are also liable to present with defiant and aggressive behaviour (i.e. to have a ’conduct disorder’), while at least one out of four is prone to depression or anxiety or has a learning disorder. The combination of ADHD and defiant-aggressive behaviour particularly affects the prognosis adversely.
The definition of ADHD is to a certain extent arbitrary. The instruments to identify the symptoms depend on societal norms, and no reliable tools exist for assessment of the associated impairment. Hence, much depends on the clinical judgement in each individual case.
The DSM IV classification of psychiatric disorders does distinguish between three subtypes of ADHD: the predominantly hyperactive-impulsive, the predominantly inattentive and the combined type. The bulk of the scientific evidence relates to the combined type, which is broadly similar to the hyperkinetic disorder defined within the ICD 10 classification. Diagnosis of this subtype depends on comparatively strict conditions relating to the seriousness, pervasiveness and persistence of the symptoms. The report in hand regarding ADHD and its treatment relates primarily to this subtype, as found in children between five and fourteen years old. There is much less evidence to support the recognition of the predominantly inattentive type or the recognition of ADHD in younger children or (young) adults. Children whose condition just falls short of the classification-criteria are considered to have a sub-threshold problem.
It is estimated that about 2 per cent of children between the age of five and fourteen display symptoms of ADHD and comorbid disorders that are sufficiently serious to warrant treatment at any given time. In the Netherlands, that equates to forty thousand children, amongst whom boys outnumber girls by four to one. In roughly one third of these cases, the symptoms persist into adulthood. About 4 per cent of the children of this age exhibit less serious or fewer symptoms of ADHD; however, their condition can also be sufficiently problematic to make intervention desirable. The diagnosis of ADHD in children from ethnic minority backgrounds appears to be inadequate.
Both the acceptance of ADHD as a psychiatric disorder and its treatment with medication generate ample social debate. It is of great importance that both the general public and the professional groups dealing with affected children have access to good information. Parent and patient support groups have a significant role to play in this context. Workers in the field of education, youth welfare and major sections of the health care sector certainly have to catch up on their knowledge.
Diagnosis and treatment
Knowledge about a child’s family circumstances and school environment should be taken into account when considering the diagnosis of ADHD, making use of information from more than one source. In addition, the presence of comorbidity should be carefully investigated. Diagnosis of the condition requires both medical and psychosocial expertise.
Intervention should be primarily aimed at reversing the negative spiral in the child’s development. Given the child’s ’difficult disposition’, the emphasis needs to be on handling the child and its behaviour and influencing the pathophysiological process by the provision of medication. The observed or imminent impairment is critical in deciding whether treatment is appropriate. All interventions should start with providing comprehensive information and psycho-education.
Two modes of treatment are known to be effective: medication, and behavioural therapy based on parent management training (PMT) and mediation training for parents and teachers. Through these forms of training, parents and teachers learn to apply certain didactic principles on a contingent, consistent and prolonged basis when dealing with the child. Cognitive therapy has not proved effective.
Medication primarily means the administration of methylphenidate, which is marketed under the name Ritalin. This is an amphetamine-like substance which, because of its addictive potential, falls within the scope of the Opium Act. There is no evidence that the drug is addictive when taken in the normal recommended dosages, but a few cases of addiction following illegal use through inhalation or injection have been reported. Methylphenidate produces an immediate discernible positive effect on the three core behavioural characteristics of ADHD in 70 to 80 per cent of children. In its present preparation, it is effective for about four hours; the number of doses per day is determined for each case individually, but two or three is adequate for most children. Some 20 to 30 per cent of recipients suffer side-effects, usually when they start taking the drug; in one out of ten, the side-effects are serious enough to suspend medication. Robust data is available regarding the safety and efficacy of the drug in the short term and in the treatment of children aged between five and fourteen. Less is known, however, about the implications of prolonged use or about methylphenidate’s long-term effects. Nor can it be assumed that the drug would have the same effect on other groups (e.g. very young children or adults) or in cases of serious comorbidity (e.g. depression, addiction or antisocial personality disorder).
With both modes of treatment, a protocol-based approach gives a considerably better outcome. In many cases, the greatest effect on the three core symptoms during the treatment period is achieved by medication combined with a carefully planned programme of information, counselling, supervision and monitoring. Intensive behavioural mediation therapy has also been found to be effective and can be sufficient on its own, especially in the less serious cases; where such therapy does not have the desired result, medication can enhance the efficacy of the treatment programme considerably. In other domains, such as social interaction, psychological well-being and academic performance, there is little difference between the two modes of treatment, other than that the effects of behavioural therapy are slightly longer-lasting. Where medication is given in combination with behavioural therapy, the drug can be administered in lower doses. Children with both ADHD and an anxiety disorder are more likely to respond to behavioural therapy. The most appropriate form of treatment should be selected for each case individually following thorough diagnostic assessment and taking account of the wishes, opinions and capacities of the parents and the environment.
Countless questions remain concerning the most effective and efficient way to proceed under various circumstances. The feasibility and cost of intervention based on behavioural therapy depends greatly on the intensity, duration and frequency of the treatment required, and on the availability of the requisite expertise. Research is urgently needed in this field.
There is no convincing evidence that short-term or continuous treatment of any kind improves the long-term prognosis for patients with ADHD. There is an urgent need for longitudinal research, partly with a view to monitoring the possible long-term side-effects of medication. Assessment of the effects of treatment should not be confined to the core symptoms.
Generally speaking, both before and after treatment, parents are more positive about treatment based upon behavioural therapy, irrespective of the outcome. There are indications, also in the Netherlands, that medication is mostly taken less than eighteen months, with a smaller group of long-term users. There are no criteria by which it is possible to determine the optimum duration of treatment or the optimum effect (as a basis for discontinuing medication). This complicates meaningful interpretation of the data on medication use.
Quantitative data on the provision of care
Research in other countries has shown that the number of ADHD-related visits to physicians has increased sharply in recent years. This is almost certainly the case in the Netherlands as well. Since about 1993, the use of Ritalin has risen enormously, both in the Netherlands and elsewhere. In 1999, the number of users under the age of nineteen was roughly thirty thousand, of whom 20 per cent were girls. The drug is most commonly used by boys aged about nine. However, usage is spreading to other groups, particularly to older children: 15 per cent of users are now more than fifteen years old. The frequency of Ritalin prescription is rising within primary ánd specialist care; there is almost no clustering of cases around certain practices.
Drug treatment is most commonly initiated by paediatricians (roughly half of all cases), followed by child psychiatrists (about a quarter of all cases). General practitioners regularly see children with psychosocial and behavioural problems and increasingly find themselves having to deal with questions regarding ADHD. The average general practitioner is involved in the administration of medication to children with ADHD two or three times a year, occasionally initiating drug treatment. Overall, general practitioners are involved in about half of all ADHD cases where medication is given; they start medication in between 6 and 20 per cent of all such cases.
The vast majority of children with ADHD attend regular primary school. Given an average class size of twenty-five children, more than half of all primary school classes will have a child with ADHD.
The quality of diagnosis and treatment
It is impossible to make any statement about the extent to which medication is prescribed appropriately and responsibly. Studies conducted in other countries indicate that in relation to ADHD, the quality of care is lacking in some respects, particularly – but by no means exclusively – in (general and pediatric) primary practice. Not enough quantitative or qualitative data is presently available regarding the care given to patients with ADHD in the Netherlands. Research is urgently needed to provide such data, embracing the fields of child psychiatry, mental health care for the young, paediatric medicine, general practice and various other medical specialisms, including (paediatric) neurology and rehabilitative care.
Guidelines and protocols have a marked positive influence on the quality of diagnosis and treatment. The Netherlands Psychiatric Association has drawn up guidelines for use by (child and youth) psychiatrists. It is highly desirable that, with the involvement of the various relevant professional associations and organisations representing patients/clients, complementary guidelines are produced to support the work of other physicians and behavioural experts. Priority should be given to guidelines for paediatricians and behavioural therapists.
These guidelines should deal with issues such as positively identifying behavioural problems to be ADHD, recognising the contributory factors, estimating the seriousness of the impairment, identifying comorbid conditions, establishing the nature and structure of psycho-education, providing information about the various forms of care available and about parent and patient support groups, referring cases to specialists, monitoring treatment (including medication) and – finally – assessing the patient’s response to medication and setting dosages accordingly. There is also a great need for exploratory diagnostic tools that are convenient to use.
As the obvious experts in this field, child and youth psychiatrists should support less specialised practitioners and make their expertise available on a consultative basis more than they do at present. First-line mental health care needs to be strengthened and it is vital that general practitioners are properly informed about the criteria for diagnosis, treatment and referral in cases involving disorders such as ADHD. To this end, in-service training is urgently needed to update the knowledge of primary care providers regarding mental health care issues in general and regarding childhood psychiatric and behavioural problems in particular, with special emphasis on exploratory diagnosis and psycho-education.
In terms of their expertise in this field, paediatricians and certain other specialists occupy an intermediate position; it is believed that the quality of and experience with diagnosis and treatment varies considerably. However, every paediatric unit should theoretically have one paediatrician with special responsibility for ADHD and a psychosocial team. Given the predominant role that paediatricians play in initiating medication in ADHD cases, both the basic training and in-service training given to paediatricians should ensure more effectively than it presently does that these specialists possess the expertise needed for the diagnosis and treatment of the condition. With a view to improving diagnosis, psycho-education and co-operation with the teaching profession and other groups, strict requirements should be formulated regarding the expertise and availability of behavioural and psychosocial experts.
The Health Council Committee believes that additional safeguards are needed in connection with the initiation of medication. General practitioners and other non-specialist doctors should only initiate medication if ADHD has been diagnosed on the basis of information from both the family and school environment, if the patient is between six and fourteen years old, if there are no serious symptoms of comorbid disorders, and if the doctor is fully aware of the methods for ascertaining the optimum dose and monitoring the effects (including any side-effects) of the medication. Medication should only be given in combination with psycho-education, pedagogical counselling, liaison with the school and, where necessary, further supervision of the child and its parents.
Quality control should be intensified in connection with the prescription of methylphenidate; this should be feasible, given that the drug is covered by the Opium Act and detailed records of its prescription therefore have to be kept. Intensive and long-term monitoring of the drug’s effects is necessary in order to obtain information about the safety of prolonged use and its long-term health implications.
Within the field of mental health care for the young and at the Youth Welfare Agencies, the diagnosis and treatment of behavioural problems is often the responsibility of professionals whose background is in psychology and behavioural therapy. Formal requirements need to be made regarding their expertise in the field of specific psychopathological diagnosis. Steps should also be taken to ensure that such professionals work according to guidelines, do not diagnose ADHD without bringing in appropriate medical expertise and consider medication timely and promptly.
For various reasons, the diagnosis of ADHD in children of less than six and in adults is more complex. There is still not enough knowledge about the most appropriate forms of medication for patients in these groups. The prescription of medication for children under six entails additional risks, while with (young) adults there is a real possibility of abuse. The diagnosis and treatment of ADHD in these groups should be left entirely to (child and youth) psychiatrists.
Medication for sub-threshold ADHD and other behavioural problems
The effect of methylphenidate is not typically limited to children with ADHD. It is also known to improve concentration and reduce impulsiveness in ’normal’ children. It is believed that the drug can benefit children with sub-threshold ADHD experiencing relatively serious problems at home, at school or in other areas of their life. There are also indications that it can diminish defiant and aggressive behaviour in children with or without symptoms of ADHD. However, its efficacy in these groups in various situations and in relation to other interventions has yet to be studied.
Surveys conducted in the US have shown that the number of cases where methylphenidate is prescribed, although the criteria for the diagnosis of ADHD are not met, is at least as great as the number of prescription cases where the criteria are met. Cases of the first kind typically involve children with sub-threshold ADHD or who display more ADHD-like behavioural characteristics and antagonistic behaviour than average, but whose behaviour is not necessarily pervasive or obviously resulting in impairment.
The use of medication for children with sub-threshold ADHD or symptoms of an defiant or aggressive behavioural disorder is not necessarily wrong, but there is a danger of inappropriate and undesirable broadening of the indication. For the time being, therefore, medication should be prescribed for these groups only under certain circumstances: in individual cases following specialised diagnosis, subject to careful psychiatric evaluation and in the context of medical research. Under any other circumstances, the ’speculative’ prescription of psychostimulants for children with non-specific behavioural problems is undesirable.
Prevention, identification and early intervention
It has been demonstrated that parenting support programs aimed at the general public can reduce the incidence of behavioural problems. It is quite possible that such programs may be beneficial in relation to ADHD, and especially in groups subject to an accumulation of non-specific risk factors. However, effects of this kind are difficult to demonstrate. No specific risk factors with any predictive value on the individual level have been identified for ADHD. Screening the (young) population for behavioural characteristics regarded as the precursors of ADHD symptoms could not therefore be justified.
The early signs of developmental problems that cause parents to raise questions regarding the upbringing of their children are often poorly differentiated and have little predictive value in relation to the actual development or nature of a specific disorder. Therefore, health care professionals often take no action, even though this can result in valuable time being lost. Yet enough is now known to suggest that early intervention on the basis of an individual request for assistance or advice on the upbringing of a child is both feasible and desirable. Such intervention would initially consist of general parenting support, with a more specific approach being subsequently adopted where necessary.
Pathways of care
There is a need for a staged identification mechanism and a range of more and less specialised intervention options with various points of entry. A system of this kind would require the involvement of numerous professions and institutions: the teaching profession, pre-school organizations, youth/school health care workers, the Youth Welfare Agencies, primary health care practitioners, paramedics, medical specialists and those providing mental health care for the young. Prompt provision of appropriate care to afflicted children and their families depends on co-operation between these players and the efficient deployment of expertise, manpower and resources. General practitioners and Youth Welfare Agencies play a key role in this context.
The early identification of problems serves little purpose if there is insufficient scope for prompt intervention or referral. Low-threshold assistance in the form of information, parenting and family support should be available to parents with concerns about the upbringing of children who display behavioural problems. The provision of such assistance is primarily a task for the youth health care sector, working closely with other organisations involved in the field, such as independent agencies for pedagogical counselling and organisations providing mental health care for the young.
As presently organised, the Youth Welfare Agencies cannot be depended upon to ensure that children with ADHD receive sufficient or appropriate care. The presence of adequate diagnostic expertise in medical and psychopathological disciplines needs to be structurally assured, and the Agencies need to work within a clear system for co-operation and referral. Their central intake-function should not form an obstacle to intercollegiate consultation.
The educational system
In many cases, the opinion of the school is crucial in relation to the identification and recognition of behavioural problems. It is important that the teaching profession is able to make a preliminary identification of pupils for whom diagnosis and treatment within the health care system or help from other sectors is indicated. In consultation with parents and — often — the school doctor, problem pupils should get timely referred to their general practitioners or the local Youth Welfare Agency. To avoid inappropriate referrals, high-quality pupil care is required, backed up by a good infrastructure and proper co-operation, as well as harmonisation of the assistance available through schools, the school (youth) health care system and the mental health care system for the young. There are good reasons for effecting such co-operation at a supra-school level (Back to School Together, WSNS).
Greater understanding of developmental pathology is required within the educational system. To this end, school supervision departments will need to increase their input and the expertise of their pupil supervisors in the field of personal assessment and guidance.
Knowledge centre
Given the large number of actors involved in the assistance of children with ADHD and their parents, and the amount that needs to be done to promote awareness of the condition and its treatment, the government is advised to promote the development of a knowledge centre in this field. The role of such a centre would be to inform health care, youth welfare and education consumers and professionals about training, treatment methods, protocols, residential care facilities and so on. The centre would need to have ties with the medical research community, but should itself have a more practical orientation. The involvement of organisations representing ADHD patients and their parents would be essential.
Scientific research and development
Research is urgently needed to gather both quantitative and qualitative data on the way ADHD is actually diagnosed and treated in the Netherlands. It is necessary to examine the way the condition is dealt with not only by child psychiatrists, but also by paediatricians, general practitioners, those providing mental health care for the young, and possibly other groups as well. In view of the social importance and complexity of any such research programme, the government should play a facilitative role. Equally important is research to explore the scope for optimising the organisation and provision of the various kinds of treatment. In this context, distinction should be made between children between five and fourteen years old, very young children, adolescents and adults. The most effective and efficient ways of using the various methods for the treatment of ADHD and sub-threshold ADHD should be investigated at the regional level, with the involvement of educational and health care institutions. Furthermore, long-term and intensive monitoring programmes are required to study the implications of prolonged methylphenidate use and to identify any late effects that the drug’s use may have.